E. M. Halvajian disclosed a combination impact cushioning bumper in his U.S. Pat. No. 3,472,332 by attaching the impact cushioning bumper and brake device to the front of an automative vehicle having an upper bumper mechanism including a bumper unit which is retractable rearwardly under impact against the yielding resistance of an energy absorbing means, and a lower vertically swingable brake mechanism which is released to swing downwardly into frictional braking contact with the roadway in response to retraction of the bumper unit.
However, this braking mechanism is only actuated upon impact with another car. If the car is running very fast, a serious collision due to a greater moment of inertia and impact force thus produced may still cause breakage or damage of the car or injury to a car driver. Such a conventional brake system can not prevent an impact accident in advance of the occurrence of car collision. In other words, it is too late to brake a car under an impact.
It is therefore expected to disclose an automatic braking system which is actuated in advance of a real collision of two cars.